1. The Field of the Invention
Implementations of the present invention relate generally to systems, apparatus, and methods for creating formable panels with light refraction properties.
2. Background and Relevant Art
Dichroism generally refers to a property in which an object absorbs or filters one of two plane-polarized components of transmitted light more strongly than the other, as well as, or, in the alternative, when an object differentially reflects or transmits light. Objects that have these types of properties, or can otherwise create this these types of effects, are referred to as being “dichroic.” In the field of architectural design, there has been some recent interest in panels that exhibit dichroic properties (i.e., “dichroic panels”) due to any number of both aesthetic and functional reasons (or both). To create a dichroic panel, a manufacturer will typically attach one or more light refracting films (or “dichroic films”) to a transparent or translucent substrate, such as a translucent or transparent glass or acrylic panel. The manufacturer can then use the dichroic panel as a window, wall, door, partition, or even as a treatment to existing structure. Unfortunately, present methods for manufacturing dichroic panels suffer from a number of disadvantages, and often lead to products with relatively poor quality.
For example, one conventional example of creating dichroic panels include those related to dichroic glass panels. In this case, a manufacturer will typically create a dichroic glass panel by nesting a dichroic film between two outer glass substrates (glass panels/sheets), and two bonding film layers (or “tie layers”). The tie layers are typically comprised of thermoplastic polyurethane (TPU), ethylene vinyl acetate (EVA), or polyvinyl butyral (PVB). In another example, a manufacturer may deposit a dichroic metallized layer or coating on the surface of a glass substrate. In this additional example, however, the dichroic surface of the glass sheet is unprotected, and the available sizes are quite limited. In addition, glass substrates generally tend to be fairly difficult to work with. For example, the density of typical glass panels can result in a substantial amount of hardware and equipment not only to handle the glass during preparation and fabrication, but also to support the weight of the finished panel during installation. In addition, it is difficult and/or expensive to add additional finishes to glass panels, such as embosses or textures. This is particularly the case with large glass panels (e.g., greater than a few feet in any dimension). For at least these and other reasons, dichroic glass panels tend to be relatively high cost.
Along these lines, the fragility and brittleness of glass panels make the use of dichroic glass panels quite limited. Although lamination of dichroic films in glass can reduce the propensity of the glass panel to shatter, lamination does not eliminate the chance that the glass lites may become cracked or spalled in the event of impact. Further, the brittle nature of laminated glass creates difficulty in fabrication, and tends to impose limitations to the extent that most fabrication of the laminated panels typically needs to be performed in a glass shop, rather than onsite at the point of installation. Specifically, it is nearly impossible to form glass panels into other shapes after processing them to create the dichroic panels. Attempts to reform dichroic glass panels, particularly without the appropriate processing equipment, would either ruin/break the glass substrates, or ruin the dichroic film/coating, or both. Although one could prepare such dichroic glass panels onsite, the necessary glass processing equipment are cumbersome, and bringing such glass processing onsite is typically not a viable option.
Additional conventional mechanisms for creating dichroic panels involve the use of substrates other than glass, such as acrylic materials. For example, one conventional dichroic acrylic panel comprises a dichroic film that is adhered to a single outer surface of an extruded acrylic sheet. Such a panel can offer a unique aesthetic, but tends to be limited in its application of use due to the dichroic film being positioned on the outer surface. In particular, the positioning of the dichroic film on the outer surface leaves the dichroic film susceptible to scratching, marring or contamination that can be unsightly. In addition, both the dichroic film and substrate can contribute to other types of problems with this kind of dichroic panel.
For example, conventional light refracting/dichroic films, which typically comprise a combination of several different ultra-thin substrate films formed together, tend not to be UV-stable. Specifically, one of the underlying substrate films used to create conventional dichroic films comprises a non-UV-stabilized polyester. Due to lack of UV-stability in the light refracting films, therefore, dichroic panels comprising dichroic film attached to an outside surface of an acrylic substrate cannot ordinarily be used in exteriors without adversely affecting the dichroic surface. Furthermore, acrylic itself tends to have relatively poor flammability performance, and local building codes often prohibit use of acrylic and other flame-propagating materials to be installed as interior finish applications. Still further, the acrylic and dichroic film combination as described above tends to produce a mirror-like reflectance, which, in context with bright lights or daylight, can have a blinding effect on an observer.
Notwithstanding such disadvantages, there are other conventional examples of acrylic in which the manufacturer alternatively positions the dichroic film between two acrylic substrates, much like with the aforementioned glass example. In this case, however, the manufacturer encapsulates a dichroic film interlayer within opposing acrylic sheet substrates using a liquid contact adhesive therebetween (rather than a bonding film or tie layer). On one hand, using a liquid contact adhesive to adhere the acrylic substrates and dichroic film can aid in reducing the cost of manufacturing process (i.e., no lamination or heat/pressure apparatus needed). There are a number of different disadvantages to using liquid adhesives, however.
For example, at least one disadvantage is that the liquid adhesive tends to distort the dichroic interlayer, at least in part since it can be difficult to remove air bubbles trapped in the liquid adhesive, and between the dichroic film and acrylic substrate(s). These and other imperfections caused by the liquid adhesive have a tendency to hinder the intended aesthetic properties of the panel, thereby limiting the panel to use in relatively low-end applications. At least another disadvantage is that such a panel will have little or no post-manufacturing formability (i.e., limited to the shape of the initial acrylic substrates). Specifically, the use of liquid/contact adhesives tends to limit the amount of bending and forming that the resulting panel can endure without delaminating. In addition, and as previously described, the use of acrylic panels means that the resultant panel cannot ordinarily be used as a building material under typical building codes that employ flammability constraints.
Although there are conventional lamination processes that apply heat and pressure (and thus do not use a liquid adhesive) with resin substrates on other types of panels, these types of processes are not readily applicable to dichroic acrylic or glass panels. Specifically, the temperatures and pressures in most conventional lamination processes are quite high (e.g., 300° F. or higher). In such processes, these higher temperatures (often accompanied with high pressures of 100 psi or greater) are used to melt the substrates to each other, and/or to some decorative interlayer. Such high temperatures and pressures, however, will tend to wrinkle, tear, or damage the dichroic film, or damage or crack the acrylic or glass substrates whether laminated to an outside surface or positioned between two acrylic or glass substrates. This tends to be particularly true when using substrates to which textures or embossing have already been applied prior to the lamination process. One will appreciate that this would make such a resulting panel unacceptable for use in most architectural design applications, where both structure and aesthetics considerations are important.